122 Experiments on the DevelojJment of 



at the Time of Sealing^ the Tubes. — The infusion in tubes 1, 2, 3, 

 6, 7 was clear and pellucid; that in tubes 4, 5, 8, 9, 10, 11 ^Yas 

 bazy. 



Microscopic examination gave tbe result indicated above, as to 

 the appearances of freshly - prepared hay and hay - and - cheese 

 infusion. 



Subsequent Appearances of the Infusion in Tubes 1-11. — The 

 tubes with infusion which was pellucid at the first were found to 

 retain this character for several weeks, being preserved in the 

 air-bath, and examined from day to day. The hazy infusions 

 were opened after four days, and their contents found to be un- 

 changed. 



A portion of the same hay-and-cheese infusion, boiled and pur- 

 posely contaminated by preservation in an uncleaned beaker, was 

 found after four days to be teeming with Bacterium termo ex- 

 hibiting vital movements. The pellucid infusions were subsequently 

 examined with the microscope at different times, and found to be 

 unchanged. 



Series B. Nov. 25th. Experiments loith Turnip-and-Cheese 

 Infusion. — An infusion was made with 700 grms. sliced white 

 turnip and 1000 grms. water, to which about 1 grm. finely- 

 minced new cheese was added, the jug containing the mixture 

 being maintained for four hours on a sand-bath at a temperature of 

 45°-55° C. 



The infusion was now filtered ; sp. gr. of the infusion 1011 • 1. 

 Eeaction slightly acid. 



Tubes 12, 13, 14. Sealed cold. Submerged in boiling water 

 for thirty minutes. 



Tubes 15, 16, 17, 18, 10. Sealed approximately during ebulH- 

 tion. Submerged in boiling water for thirty minutes. 



The tubes were preserved in the air-bath as in Series A. 



Microscopic and Nahed-Eye Appearances of the Infusion at the 

 Time of Sealing the Tubes. — The liquid in all the tubes was per- 

 fectly clear and limpid. A few shreds and flakes were obvious, 

 which appeared to be derived from the filter paper and from the 

 slight precipitation of albuminous matter. The microscopic ap- 

 pearances were those above described as characterizing such in- 

 fusions. 



Subsequent Appearances of the Infusion. — The infusion in all 

 the tubes was found on examination from day to day to retain its 

 limpidity. Subsequent microscopic examination of all the tubes at 

 various periods subsequent to the closure of the tubes (from four 

 clays to three weeks) yielded no indication whatever of a develop- 

 ment of Bacteria or other organisms, nor of any change. A por- 

 tion of the same infusion placed in an uncleansed beaker for com- 

 parison was milky and swarming with Bacteria after three days. 



